Two major breakthroughs in autoimmune necrotizing myositis

Autoimmune necrotizing myositis (AINM) is a recently described entity related to the deleterious effect of autoantibodies directed against an enzymeProtéine capable d’activer une réaction biochimique précise., HMG CoA reductase, most often in the context of prolonged statin exposure. Israeli researchers report the observation, at this unique stage, of a family of Bedouin origin in whom :

• a homozygous mutationModification soudaine et transmissible du matériel génétique. Elle peut être spontanée ou induite par des agents dits » mutagènes » (radiations, produits toxiques,…). in the gene coding for HMGCoA reductase resulted in a late-onset and rapidly progressive limb-girdle muscular dystrophy.
• The same researchers synthesised and purified the metabolite of HMG-CoA reductase, mevalonolactone, and were able to demonstrate its clinical efficacy, both in this family and in the mouse model of AINM.

This highly original work holds great promise for the treatment of AINM.

Limb girdle muscular disease caused by HMGCR mutation and statin myopathy treatable with mevalonolactone. Yogev Y, Shorer Z, Koifman A et al. Proc Natl Acad Sci U S A. 2023 Feb.